Hickok testers are considered the best but can be very expensive,
I have a Eico 667 which is popular and can be had on Ebay for about $200. Since these units are 50 to 60 years old they may updating and mods. There is lots info on the web.
I have a Eico 667 which is popular and can be had on Ebay for about $200. Since these units are 50 to 60 years old they may updating and mods. There is lots info on the web.